【BZOJ1014】火星人prefix(splay,Hash)

题意:

思路:

 

  1 const mo=9000011;
  2 var t:array[0..200000,0..1]of longint;
  3     sum,size,fa,a,b,id,mi:array[0..200000]of longint;
  4     n,m,i,x,y,s,k,j,cnt,root:longint;
  5     ch:ansistring;
  6  
  7 procedure swap(var x,y:longint);
  8 var t:longint;
  9 begin
 10  t:=x; x:=y; y:=t;
 11 end;
 12  
 13 procedure pushup(x:longint);
 14 var l,r:longint;
 15 begin
 16  l:=t[x,0]; r:=t[x,1];
 17  size[x]:=size[l]+size[r]+1;
 18  sum[x]:=(sum[l]+int64(mi[size[l]])*b[x]+int64(mi[size[l]+1])*sum[r]) mod mo;
 19  // sum[x]:=(sum[r]+int64(mi[size[r]])*b[x]+int64(mi[size[r]+1])*sum[l]) mod mo; 也可以
 20 end;
 21  
 22 function min(x,y:longint):longint;
 23 begin
 24  if x<y then exit(x);
 25  exit(y);
 26 end;
 27  
 28 procedure rotate(x:longint;var k:longint);
 29 var y,z,l,r:longint;
 30 begin
 31  y:=fa[x]; z:=fa[y];
 32  if t[y,0]=x then l:=0
 33   else l:=1;
 34  r:=l xor 1;
 35  if y<>k then
 36  begin
 37   if t[z,0]=y then t[z,0]:=x
 38    else t[z,1]:=x;
 39  end
 40   else k:=x;
 41  fa[x]:=z; fa[y]:=x; fa[t[x,r]]:=y;
 42  t[y,l]:=t[x,r]; t[x,r]:=y;
 43  pushup(y);
 44  pushup(x);
 45 end;
 46  
 47 procedure splay(x:longint;var k:longint);
 48 var y,z:longint;
 49 begin
 50  while x<>k do
 51  begin
 52   y:=fa[x]; z:=fa[y];
 53   if y<>k then
 54   begin
 55    if (t[y,0]=x)xor(t[z,0]=y) then rotate(x,k)
 56     else rotate(y,k);
 57   end
 58    else k:=x;
 59   rotate(x,k);
 60  end;
 61 end;
 62  
 63 procedure build(l,r,x:longint);
 64 var mid,now,last:longint;
 65 begin
 66  if l>r then exit;
 67  now:=id[l]; last:=id[x];
 68  if l=r then
 69  begin
 70   sum[now]:=a[now]; b[now]:=a[now];
 71   fa[now]:=last; size[now]:=1;
 72   if l<x then t[last,0]:=now
 73    else t[last,1]:=now;
 74   exit;
 75  end;
 76  mid:=(l+r)>>1; now:=id[mid];
 77  build(l,mid-1,mid);
 78  build(mid+1,r,mid);
 79  b[now]:=a[mid]; fa[now]:=last;
 80  pushup(now);
 81  if mid<x then t[last,0]:=now
 82   else t[last,1]:=now;
 83 end;
 84  
 85 function kth(x:longint):longint;
 86 var k,tmp:longint;
 87 begin
 88  k:=root;
 89  while k<>0 do
 90  begin
 91   tmp:=size[t[k,0]]+1;
 92   if tmp=x then exit(k);
 93   if tmp>x then k:=t[k,0]
 94    else
 95    begin
 96     x:=x-tmp;
 97     k:=t[k,1];
 98    end;
 99  end;
100 end;
101  
102 function query(k,tot:longint):longint;
103 var x,y:longint;
104 begin
105  x:=kth(k); y:=kth(k+tot+1);
106  splay(x,root);
107  splay(y,t[x,1]);
108  exit(sum[t[y,0]]);
109 end;
110  
111 function ask(x,y:longint):longint;
112 var l,r,mid,last:longint;
113 begin
114  l:=1; r:=min(cnt-x,cnt-y)-1; last:=0;
115  while l<=r do
116  begin
117   mid:=(l+r)>>1;
118   if query(x,mid)=query(y,mid) then begin last:=mid; l:=mid+1; end
119    else r:=mid-1;
120  end;
121  exit(last);
122 end;
123  
124 procedure ins(x,y:longint);
125 var p,q,z:longint;
126 begin
127  p:=kth(x+1);
128  q:=kth(x+2);
129  splay(p,root);
130  splay(q,t[p,1]);
131  inc(cnt); z:=cnt; t[q,0]:=z;
132  fa[z]:=q; b[z]:=y;
133  pushup(z);
134  pushup(q);
135  pushup(p);
136 end;
137  
138 begin
139  
140  readln(ch);
141  n:=length(ch);
142  for i:=2 to n+1 do a[i]:=ord(ch[i-1])-ord('a')+1;
143  mi[0]:=1;
144  for i:=1 to 150000 do mi[i]:=mi[i-1]*27 mod mo;
145  for i:=1 to n+2 do id[i]:=i;
146  build(1,n+2,0); root:=(n+3)>>1; cnt:=n+2;
147  readln(m);
148  for i:=1 to m do
149  begin
150   readln(ch); k:=length(ch); s:=0; x:=0; y:=0;
151   for j:=3 to k do
152   begin
153    if ch[j]=' ' then begin inc(s); continue; end;
154    if s=0 then x:=x*10+ord(ch[j])-ord('0');
155    if s=1 then y:=y*10+ord(ch[j])-ord('0');
156   end;
157   if ch[1]='Q' then writeln(ask(x,y));
158   if ch[1]='R' then
159   begin
160    y:=y+ord('0')-ord('a')+1;
161    k:=kth(x+1); splay(k,root);
162    b[k]:=y; pushup(root);
163   end;
164   if ch[1]='I' then
165   begin
166    y:=y+ord('0')-ord('a')+1;
167    ins(x,y);
168   end;
169  end;
170  
171 end.

 

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posted on 2017-04-11 19:21  myx12345  阅读(134)  评论(0编辑  收藏  举报

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